Jadefire

It wasn't exactly 1000 years ago, it was 1000-ish years ago. Same with how the 100 year war actually lasted about 116-ish years, and the war of 1812 lasted from 1812 - 1814. Most likely, the Crystal Empire was actually banished for, say, 1008 years. It wasn't that Sombra placed a "dissappear for a thousand years" curse, but rather more likely a "be voided from reality" curse that took a really long time to wear off. In fact, events from that time period are pretty fluid to begin with. Discord arrived and plunged Equestria into chaos, which necessitated him tasting the rainbow. Tirek and Scorpan happened first, yet Tirek knew who Discord was. Scorpan also met Star Swirl the Bearded if I'm remembering correctly, and Star Swirl was apparently alive during the founding of Equestria. In addition, it's also implied in the show that Luna knew Star Swirl as well. (It's confirmed in the comics, by the way, but the canonicity of the comics to the show itself hasn't been confirmed that I'm aware of.) Anyway, this all likely means that all these people were doing their thing over a period of time. In fact, the only character who probably did get banished for exactly 1000 years was Nightmare Moon, given the prophecy that the "the stars will aid in her escape" on the summer solstice of the 1000th year. Everyone else probably just got banished "for a really long time" that happened to be roughly within a decade of 1000 years.

Only if Fluttershy is involved.

There was a comic where Fluttershy performed a Sonic Rainboom. Instead of being rainbow, it was yellow and pink, and spontaneously generated a cloud of butterflies.